Anti-IPO-38 is suitable for ELISA, immunoprecipitation, western blotting and immunohistochemistry (frozen and formalin/paraffin). The antibody is reported to recognize a nuclear antigen that is present in the cytoplasm and nuclei of proliferating cells (paraformaldehyde fixed, Triton X-100 permeabilized). An increase of 400% is observed in cells in mitosis (determined by analysis of K562 cells synchronized with colcemid). IPO-38 does not block the binding of the Ki-67 antibody. Tonsillar tissue is typically used as a positive control.